# Recent content by Drizzy

1. ### Change in EMF due to falling magnet

1. Homework Statement My problem is trying to understand this graph and explain why it changes the way it does 2. Homework Equations e=change in ∅/change in time 3. The Attempt at a Solution I know that the magnetic field increases/decreases when the magnet is on the way into the coil and...
2. ### Spring in motion

I have a question. If I hang a weight on a spring it will get delta L meters longer. then the weight starts to bounce up and down (the amplitude is y meters). (it was hard to make the upper y distance equal to the y on the bottom but they are supposed to be equal. So my question is: when the...
3. ### Angle of electron in an electric field

1. Homework Statement https://imgur.com/zEoCpc0 I am trying to figure put the angle and my attempt is tanx=sy/sx (I have calculated a value for the distances) But my book is saying: tanx =vy/vx I don't understand why my way of solving it is wrong... I dont get the same answer for x :/

yes

0.0063998689
6. ### Determining hole size using laser interference

1. Homework Statement Lisa makes a hole in aluminum foil. She wants to know the diameter of the hole. She points a laser through the hole. That picture is what appears on the wall that is 1,25 meters behind the aluminum. the distance between every circle is 8mm. the wave length is 633nm...
7. ### Emittance from an object

My guess is thatn objectsens out wavelengths that correspond to the light that makes the elctron excited. So if we have an object that can get excitet from every wavelength then it is going to sens out light with every wavelength

9. ### Emittance from an object

https://imgur.com/gallery/DZOee?_branch_match_id=335507368389835137
10. ### Emittance from an object

https://imgur.com/gallery/DZOee?_branch_match_id=335507368389835137 1. Homework Statement Can anybody explain this picture? My guess is: the object emits every wave-length but it emits more wavelengths or more light from the colour that the peak is at. Is this correct? Why does the object emit...
11. ### How many slits for a discrete spectrum?

1. Homework Statement I watched two videos on KhanAcademy, one was about light interference with 2 slits and the other was with 4 slits. The video with 2 slits got a continuous spectrum whereas the one with 4 slits got a discrete spectrum. So my question is: how many slits does it take to get...
12. ### Noise level which formula?

If I and I0 are given and I calculate the value of L, what is L giving me? Is it the noise level when the intensity is I or is it the noise level difference from when it goes from I0 to I?
13. ### Noise level which formula?

1. Homework Statement When the distance to a sound source is doubled, the noise level will be halved. Yes or no? 2. Homework Equations L = 10 lg(I/10-12) or L = 10 lg(I/l0) 3. The Attempt at a Solution my book used the first formula in another question and it used the second one in this...
14. ### Alternating current generator

"You can see that the magnetic field lines run vertically. If the coil is also laid vertically, it lays in line with the field lines and don't cut them, so no current is induced. If no current is induced the voltage is 0." How on earth can anybody explain that the coil in position A is lined up...
15. ### Alternating current generator

why cant I use the right hand rule?